Fig. 4

Mandible of P. boisei. Seen from the top, this specimen, from Lake Natron in Tanzania, preserves molar teeth that are each approximately as large as a thumbnail. Note that the premolar teeth (in this view, above the three molar teeth on each side of the jaw) are nearly as large as the molar teeth. In comparison, the incisor and canine teeth towards the front of the jaw are tiny. The body of the mandible holding the molars and premolars is extremely thick and robust. Image by Bob Campbell, courtesy of Bernard Wood